using Microsoft.AspNetCore.Http;
using Netmash.Security.Authentication.Tuitio.Abstractions;
using Netmash.Security.Authentication.Tuitio.Extensions;
using Newtonsoft.Json;
using System;
using System.Collections.Generic;
using System.Linq;
using System.Security.Claims;
using Tuitio.PublishedLanguage.Dto;
using c = Netmash.Security.Authentication.Tuitio.Constants;

namespace Netmash.Security.Authentication.Tuitio.Services
{
    internal class UserContextAccessor : IUserContextAccessor
    {
        private readonly IHttpContextAccessor _httpAccessor;

        public UserContextAccessor(IHttpContextAccessor httpAccessor)
        {
            _httpAccessor = httpAccessor;
        }

        public bool UserIsLoggedIn => _httpAccessor.HttpContext.User != null;
        public string UserId => GetUserClaim<string>(ClaimTypes.NameIdentifier, true, true, "User id");
        public string UserName => GetUserClaim<string>(ClaimTypes.Name, true, true, "User name");
        public IEnumerable<(int id, string code)> UserGroups
        {
            get
            {
                var groups = GetUserClaim<IEnumerable<RecordIdentifier>>(c.ClaimTypes.UserGroups, false, false);
                return groups.ToTuples();
            }
        }

        public IEnumerable<(int id, string code)> UserRoles
        {
            get
            {
                var roles = GetUserClaim<IEnumerable<RecordIdentifier>>(c.ClaimTypes.UserRoles, false, false);
                return roles.ToTuples();
            }
        }

        public bool IsAnonymousGuest => GetUserClaim<bool>(c.ClaimTypes.IsAnonymousGuest);

        private T GetUserClaim<T>(string claimType, bool isMandatory = false, bool isPrimitiveType = true, string claimLabel = null)
        {
            var claimValue = _httpAccessor.HttpContext.User?.Claims.FirstOrDefault(z => z.Type == claimType)?.Value;
            if (string.IsNullOrEmpty(claimValue))
            {
                if (isMandatory)
                    throw new Exception($"{claimLabel ?? claimType} could not be retrieved from claims.");
                else
                    return default;
            }

            try
            {
                if (isPrimitiveType)
                    return (T)Convert.ChangeType(claimValue, typeof(T));
                else
                    return JsonConvert.DeserializeObject<T>(claimValue);
            }
            catch (Exception ex)
            {
                throw new Exception($"Failed to convert claim {claimLabel ?? claimType} to type {typeof(T).Name}.", ex);
            }
        }
    }
}